The present invention relates generally to weather stripping and more specifically to a deformable weather stripping especially useful in sealing and thermally insulating the space or gap between a window jamb and a rough opening of a window.
Modern construction techniques in both commercial and residential buildings typically rely on the use of prefabricated windows. Such prefabricated windows are installed in a "rough" opening in the wall which is dimensionally similar to the dimensions of the prefabricated window. A slight gap of up to one inch between the window edges or jambs and the rough opening is typically allowed to account for variations in measurement error and workmanship. Shims, typically made of scrap wood, are usually inserted to fill the gaps and to provide structural support.
Various forms of thermal insulating material, such as fiberglass, solid or liquid foam, paper products and the like are "stuffed" or "blown" into the gap area to fill the void. Caulking material is then applied around the gap to form a weather-tight seal and decorative trim is applied to hide the caulking.
Known methods for sealing the gap between the window jamb and the rough opening, such as insertion of fiberglass insulation into the gap, are time consuming and imprecise. Such a method may require between twenty to thirty minutes to insert the fiberglass and apply the caulking or bonding material. A worker must use a tool, such as a screwdriver or a spatula, to essentially fold the fiberglass material along an imaginary centerline and "stuff" it into the gap. Since the fiberglass is generally bent in half, the half sections tend to shift and twist when inserted using the tool such that uneven portions of insulation are wedged into the gap. Insertion in such a manner causes the material to twist and deform asymmetrically leading to nonuniform distribution of insulation within the gap.
If the gaps are particularly wide, it becomes difficult to hold the fiberglass in place within the gap while adding additional fiberglass. This increases installation time and cost. Since is it difficult to apply the fiberglass uniformly within the gap, the thermal insulation value along the gap varies.
Furthermore, all buildings shift and settle in time causing movement along beams and within wall structures. This often causes the gap between the window jamb and the rough opening to shift or slightly change shape. Fiberglass insulation, which has been stuffed into the gap, does not conform to such dimensional changes in the size of the gap causing the insulation to essentially pull away from either the window jamb or the border of the rough opening. This results in a reduced thermal insulation value and higher energy costs.
The caulking or bonding material applied to the gap to fully seal the gap is even more intolerant of building settling. Small dimensional changes in the size of the gap cause the caulking to crack and split, thus possibly allowing air flow through the gap, again reducing insulation value. Cracked caulking may also allow water vapor to pass through the gap, thus causing condensation problems.
In addition to building settling, wood structures tend to swell and shrink depending on climatic conditions, seasonal changes and the progression of time. Such changes compound the problems associated with the use of fiberglass insulation and caulking.
Furthermore, use of fiberglass insulation may give rise to environmental concerns. Workers using fiberglass products typically must, at least, wear a face mask. Contact between fiberglass insulation products and the skin is also ill-advised as it may be extremely irritating and may cause skin rashes. Use of liquid foam insulation also raises environmental concerns as the liquid vapors are toxic and must be avoided.
Known hard rubber and foam products have been used to seal joints between roadway sections, pavement and expansion joints. However, such hard rubber products are not well-suited for thermally insulating and sealing the gap between the window jamb and the rough opening of the window since they can not adequately deform to the dimensional changes associated with window installation. Further, such hard rubber products cannot be compressed without causing damage or deformation of the wooden or thin metal window structures.
Accordingly, it is a object of the present invention to substantially overcome the above-described problems.
It is another object of the present invention to provide a compressible foam weather stripping that deforms and compresses to fill a gap between a window jamb and a rough window opening.
It is a further object of the present invention to provide a compressible foam weather stripping that uniformly thermally insulates a gap between a window jamb and a rough window opening and eliminates the need for caulking compound.
It is also an object of the present invention to provide a compressible foam weather stripping that accommodates changes in gap size due to building settling and material swelling and shrinking.
It is still another object of the present invention to provide a compressible foam weather stripping that is easy and quick to install using a simple tool.
It is yet another object of the present invention to provide a compressible foam weather stripping that can be used in a wide variety of gap sizes and in non-uniform gaps.